Codeforces Round #429 (Div. 2)：A. Generous Kefa

题目：

One day Kefa found n baloons. For convenience, we denote color ofi-th baloon as s_i — lowercase letter of the Latin alphabet. Also Kefa hask friends. Friend will be upset, If he get two baloons of the same color. Kefa want to give outall baloons to his friends. Help Kefa to find out, can he give out all his baloons, such that no one of his friens will be upset — print «YES», if he can, and «NO», otherwise. Note, that Kefa's friend will not upset, if he doesn't get baloons at all.

Input

The first line contains two integers n and k (1 ≤ n, k ≤ 100) — the number of baloons and friends.

Next line contains string s — colors of baloons.

Output

Answer to the task — «YES» or «NO» in a single line.

You can choose the case (lower or upper) for each letter arbitrary.

Examples

Input

4 2aabb

Output

YES

Input

6 3aacaab

Output

NO

Note

In the first sample Kefa can give 1-st and 3-rd baloon to the first friend, and2-nd and 4-th to the second.

In the second sample Kefa needs to give to all his friends baloons of colora, but one baloon will stay, thats why answer is «NO».

题意：有n个气球，每个气球的颜色为一个小写字母，现在要把这些气球分给k个人，要求每个人不能有相同颜色的气球

思路：简单题。只要拥有的每种气球颜色数量不超过k就行了~

code：

#include<bits/stdc++.h>using namespace std;char s[105];int b[99];int main(){        int n,k,i;        while(~scanf("%d%d%s",&n,&k,s)){                memset(b,0,sizeof(b));                for(i=0;s[i];i++) b[s[i]-'a']++;                for(i=0;i<26;i++) if(b[i]>k) break;                if(i==26) puts("YES");                else puts("NO");        }        return 0;}